Bismis-2016 Abstract Book

Bismis-2016 Abstract Book

BISMiS-2016 Abstract Book Third Meeting of Bergey's International Society for Microbial Systematics on Microbial Systematics and Metagenomics September 12-15, 2016 | Pune, INDIA PUNE UNIT Abstracts - Opening Address - Keynotes Abstract Book | BISMiS-2016 | Pune, India Opening Address TAXONOMY OF PROKARYOTES - NEW CHALLENGES IN A GLOBAL WORLD Peter Kämpfer* Justus-Liebig-University Giessen, HESSEN, Germany Email: [email protected] Systematics can be considered as a comprehensive science, because in science it is an essential aspect in comparing any two or more elements, whether they are genes or genomes, proteins or proteomes, biochemical pathways or metabolomes (just to list a few examples), or whole organisms. The development of high throughput sequencing techniques has led to an enormous amount of data (genomic and other “omic” data) and has also revealed an extensive diversity behind these data. These data are more and more used also in systematics and there is a strong trend to classify and name the taxonomic units in prokaryotic systematics preferably on the basis of sequence data. Unfortunately, the knowledge of the meaning behind the sequence data does not keep up with the tremendous increase of generated sequences. The extent of the accessory genome in any given cell, and perhaps the infinite extent of the pan-genome (as an aggregate of all the accessory genomes) is fascinating but it is an open question if and how these data should be used in systematics. Traditionally the polyphasic approach in bacterial systematics considers methods including both phenotype and genotype. And it is the phenotype that is (also) playing an essential role in driving the evolution. The criteria used for systematics may change, when we have a full insight into the complexity of the genomes (and the "phenome”) of microorganisms. However, the maintenance of stable, workable and predictable taxonomic and nomenclatural standards is even more important in these times of “high-throughput” techniques. 2 Abstract Book | BISMiS-2016 | Pune, India Keynote 1 USE OF GENOME SEQUENCE DATA IN BACTERIAL TAXONOMY: PERSPECTIVES FROM LARGE SCALE ANALYSIS Jongsik Chun* School of Biological Sciences and ChunLab, Inc., Seoul National University, Seoul 08826, Republic of KOREA Email: [email protected] Next generation sequencing (NGS) and accompanying bioinformatics has lowered the technical and economical barriers that have prevented microbiologists from using genome sequence data in various research areas, including bacterial taxonomy. The genome is the ultimate source of information that can be used in all taxonomic levels, from defining new phyla to resolving the transmission of a bacterial clone between patients. Even though it is clear that genomics will play a key role in classification and identification of Bacteria and Archaea, the detailed methodology is not well established. As of July 2016, almost 70,000 genomes, as assemblies, are available in public database for Bacteria and Archaea of which ~98% are bacteria. In addition, a large quantity of genome data is also being accumulated as a form of raw data generated by conventional and new NGS systems. As in the case of 16S rRNA gene database, data and metadata of genome database for taxonomic use should be carefully curated and timely updated. It is also crucial to develop adequate and affordable (in terms of computing cost) bioinformatics tools, either as standalone software or web-services. In this talk, I will review the bioinformatics strategy for genome-based classification and identification, and introduce new integrated database for 16S rRNA gene and genome sequences (EzBioCloud). In addition, new web-based tool to detect possible contamination of genome data, named ContEst16S (http://tool.ezbiocloud.net/contest16s/) will be introduced. The presentation file can be requested to [email protected]. 3 Abstract Book | BISMiS-2016 | Pune, India Keynote 2 CULTIVATION-INDEPENDENT GENOMICS APPROACHES AND THEIR RELEVANCE TO MICROBIAL TAXONOMY B.P. Hedlund* School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154, USA Email: [email protected] A vast diversity of Bacteria and Archaea exists in nature that has evaded axenic culture. For example, meta-analysis of high-throughput 16S rRNA gene surveys of terrestrial geothermal systems worldwide (n = 372) suggest very high relative abundances of yet-uncultivated phyla (푥̅ = 16.8%), classes (푥̅ = 34%), orders (푥̅ = 42.1%), and families (푥̅ = 46.9%) [1]. Single-cell genomics, metagenomics, and a variety of molecular microbial ecology approaches provide ever-improving insight into the biology of these organisms; however, due to the International Code of Nomenclature of Prokaryotes, yet-uncultivated microorganisms are not accommodated in formal taxonomy regardless of the quantity or quality of data. Meanwhile, efforts to calibrate the existing taxonomy with phylogenetic anchors and genomic data are increasingly robust. The current climate provides an exciting opportunity to leverage rapidly expanding single-cell genomics and metagenomics datasets to improve the taxonomy of Bacteria and Archaea. However, this opportunity must be weighted carefully in light of the strengths and limitations of these approaches. We favor use of the Candidatus taxonomy to include taxa that are described genomically, particularly when genomic work is coupled with advanced molecular ecology approaches to probe metabolic functions in situ [2]. This system preserves the rigor and value of traditional microbial systematics while enabling growth of a provisional taxonomic structure to facilitate communication about "dark" lineages on the tree of life. References [1] Hedlund, B.P., Murugapiran, S.K., Alba, T.W., Levy, A., Dodsworth, J.A., Goertz, G.B., Ivanova, N., Woyke, T. (2015) Uncultivated thermophiles: current status and spotlight on 'Aigarchaeota'. Current Opinion in Microbiology 25:136-45. [2] Hedlund, B.P., Dodsworth, J.A., Staley, J.T. (2015) The changing landscape of microbial biodiversity exploration and its implications for systematics. Systematic and Applied Microbiology 38:231-236. 4 Abstract Book | BISMiS-2016 | Pune, India Keynote 3 COMMUNITY WIDE INSIGHTS INTO STRESSED NICHES USING METAGENOMIC APPROACH Rup Lal* Molecular Biology Laboratory, Department of Zoology, University of Delhi, Delhi 110007, India Email: [email protected] Here, we have utilized the potential of stressed niches in terms of analyzing diversity at species and strain level resolution to further understand the population dynamics via metagenomics. We have looked into two significantly stressed sites i.e. Hexachlorocyclohexane (HCH) dumpsite (450 mg HCH per g soil) and Himalayan hot springs (surface temperature > 95°C). At HCH contaminated sites, the combination of the genomes of two genetic subspecies (Sphingobium japonicum UT26 and Sphingobium indicum B90A) capable of degrading HCH, with metagenomic data enabled the reconstruction and validation of the last-common ancestor (LCA) genotype. Along the same line at the Hot spring sites, we were able to reconstruct two novel genomes of potential predator (Bdellovibrio bacteriovorus) and prey (Enterobacter cloacae). These data were used to construct a theoretical model describing potential predator avoidance strategies, whereby the E. cloacae strains can move between anaerobic and aerobic niches by quorum sensing population size, which is modulated by a ‘kill the winner’ viral mechanism and predation by the obligate aerobe, B. bacteriovorus. 5 Abstract Book | BISMiS-2016 | Pune, India Keynote 4 THE VALUE OF CULTURES TO MODERN MICROBIOLOGY B. Austin* Institute of Aquaculture, University of Stirling, Stirling FK9 4LA, Scotland, UK Email: [email protected] Since the late nineteenth century, the acquisition of pure bacterial cultures has been central to all facets of microbiology. Microbial pathology is no exception insofar as the goal of disease diagnostics and research is the acquisition of pure cultures of the pathogen. The basic premise is that pathological material may be inoculated onto a solid [usually gelled with agar] or into a liquid medium with incubation for a pre-determined interval when individual cells of the pathogen will be cloned into dense culture growth, which will then be subjected to further study. However, the range of media used by bacteriologists is restricted, and often centres on nutrient agar/broth, tryptone soya agar/broth and/or brain heart infusion agar/broth. Moreover, the incubation regimes may have little relevance to the growth conditions of the diseased animal. However, the desired outcome is the presence of dense virtually pure growth, which is taken as indicative of recovery of the pathogen. Unfortunately at best, a snap shot of the disease is obtained, and it may not be possible to decide if only one organism instigated the infection, and then contributed to the development of overt disease signs. It is unlikely that culturing on a single occasion would identify microbial population succession within a disease cycle. Also, conventional techniques are unlikely to recognise when two or more discrete organisms working synergistically to produce a single pathology. This situation has been observed with ulcerative conditions in cyprinids when Aeromonas salmonicida and A. hydrophila/A. sobria may be involved together, with the former instigating infection, and the latter leading to the developing of large ulcers. Certainly, it is realized that not all cells will multiply sufficiently

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